public void run()
{
// if everything in critical section was OK
// send "release" message to the coordinator
Client client = new Client(Server.getInstance().getSocketAddress(), Utils.getDefaultSocketAddress());
try
{
node = client.nodeList.Values.Last();
node.sendMessage("release", client.getIP());
}
catch (Exception e)
{
Console.WriteLine("Exception while calling method"
+ " RequestProcessor.sendMessage "
+ "with message RELEASE\n");
}
}
/// <summary>
/// Master node election.
/// </summary>
/// <param name="actionStarterIPBundle"></param>
/// <returns></returns>
public string startElection(string actionStarterIPBundle)
{
resultStringToBeReturned = "";
Client starterClient = null;
//split the string
string[] components = actionStarterIPBundle.Split(',');
string action = components[0];
string starterIP = components[1];
try
{
// we will handle master election in two cases.
if (action.Equals("join", StringComparison.InvariantCultureIgnoreCase))
{
starterClient = Server.getInstance().getClientByIP(starterIP);
}
else if (action.Equals("signOff", StringComparison.InvariantCultureIgnoreCase))
{
starterIP = Server.getInstance().getFirstRemainingClient().getIP();
starterClient = Server.getInstance().getClientByIP(starterIP);
}
}
catch (ArgumentOutOfRangeException ex)
{
resultStringToBeReturned += "There is no client in the network "
+ "please join at least one" + "\n";
}
clientsPriorities = new int[Server.getInstance().getClients().Count];
clientsStatuses = new bool[Server.getInstance().getClients().Count];
numberOfClients = Server.getInstance().getClients().Count;
int index = 0;
//now assign clientsPriorities and clientStatuses
foreach (Client client in Server.getInstance().getClients())
{
clientsPriorities[index] = client.getPriority();
clientsStatuses[index] = client.isStatus();
index++;
}
if (starterClient != null)
{
//priority is the same as the index + 1 of client in 'clients' list
elect(starterClient.getPriority());
//set this coordinator as master node
//coordinator number starts from 1, so we need index it to start from zero
Client masterClient = Server.getInstance().getClients()[coordinatorNumber - 1]; // CHECK - done!
masterClient.setMasterNode(true);
resultStringToBeReturned += "Final coordinator is node " + coordinatorNumber + " with IP " + masterClient.getIP() + "\n";
return(resultStringToBeReturned);
}
else
{
resultStringToBeReturned += "There is no starter client with given"
+ " properties to start master election" + "\n";
return(resultStringToBeReturned);
}
}
static void Main(string[] args)
{
Client client = null;
IRequestProcessor node;
bool joinOK = false;
bool signOffOK = false;
Console.WriteLine("Enter server's socket address - IP:PORT ");
string serverSocketAddress = Console.ReadLine();
while (true)
{
if (Utils.isValidSocketAddress(Utils.getIPFromSocketAddress(serverSocketAddress)))
{
break;
}
else
{
serverSocketAddress = Console.ReadLine();
}
}
Server server = Server.getInstance(serverSocketAddress);
server.start();
while (true)
{
Console.WriteLine("Press ENTER to continue...");
try
{
Console.ReadLine();
showCommands();
}
catch (IOException e)
{
server.stop();
break;
}
int command = int.Parse(Console.ReadLine());
switch (command)
{
case 1:
{
if (server.isNetworkAvailable())
{
Console.WriteLine("Enter socket address of new host in form IP:PORT, that you want to join: ");
string socketAddress = Console.ReadLine();
while (true)
{
if (Utils.isValidSocketAddress(Utils.getIPFromSocketAddress(socketAddress)))
{
if (checkHostEligibility(Utils.getIPFromSocketAddress(socketAddress)))
{
Console.WriteLine("Host is already in the network! Type in another IP:PORT ");
socketAddress = Console.ReadLine();
}
else
{
break;
}
}
else
{
socketAddress = Console.ReadLine();
}
}
try
{
client = new Client(server.getSocketAddress(), socketAddress);
}
catch (Exception e)
{
Console.Error.WriteLine("Error Setting the server url for this client.");
client = null;
}
if (client != null)
{
object response = null;
beautifyOutput();
try
{
node = client.nodeList.Values.Last();
response = node.joinNode(client.getSocketAddress());
Console.WriteLine(response);
try
{
// propagatemessagetoall in java
response = node.propagateJoinRequest(client.getSocketAddress());
Console.WriteLine(response);
checkClients();
beautifyOutput();
joinOK = true;
}
catch (Exception e)
{
Console.Error.WriteLine("Failed to broadcast join request");
}
}
catch (Exception e)
{
Console.Error.WriteLine("Error executing join request, response is null");
}
if (joinOK)
{
Console.WriteLine("Master node Election ");
try
{
node = client.nodeList.Values.Last();
response = node.startElection("join" + "," + client.getIP());
if (response != null)
{
Console.WriteLine(response);
//propagatemessagetoall in java
response = node.propagateCoordinatorMessage(client.getIP());
Console.WriteLine(response);
beautifyOutput();
}
// Master election is done. because of it joinOK is false now.
joinOK = false;
}
catch (Exception e)
{
Console.Error.WriteLine("Failed to broadcast coordinator message");
}
}
}
else
{
Console.WriteLine("Try to correct server's socket address"
+ " or clients' socket address");
break;
}
}
else
{
Console.WriteLine("Please first add your server to the network");
}
break;
}
case 2:
{
if (server.isNetworkAvailable())
{
bool isOneHostAvailable = false;
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
node = client.nodeList.Values.Last();
object response = node.atLeastOneHostAvailable();
isOneHostAvailable = (bool)response;
}
catch (Exception e1)
{
Console.WriteLine("Exception in executing method "
+ "RequestProcessor.atLeastOneHostAvailable");
}
if (isOneHostAvailable)
{
showNetwork();
Console.WriteLine("Enter the node ID to sign it off from the network:");
int nodeIdToSignOff = int.Parse(Console.ReadLine());
while (nodeIdToSignOff == 0)
{
Console.WriteLine("Server cannot be signed off from the network!" + "\n");
Console.WriteLine("Enter the node ID to sign it off from the network: ");
nodeIdToSignOff = int.Parse(Console.ReadLine());
}
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
}
catch (Exception e)
{
Console.Error.WriteLine("Error Setting the server url for this client.");
client = null;
}
if (client != null)
{
object response = null;
beautifyOutput();
try
{
node = client.nodeList.Values.Last();
response = node.signOffNode(nodeIdToSignOff);
Console.WriteLine(response);
try
{
response = node.propagateSignOffRequest(nodeIdToSignOff);
Console.WriteLine(response);
beautifyOutput();
signOffOK = true;
}
catch (Exception e)
{
Console.WriteLine("Failed to broadcast signoff request");
}
}
catch (Exception e)
{
Console.WriteLine("Error executing signoff request, response is null");
}
if (signOffOK)
{
Console.WriteLine("Master Node Election: ");
try
{
node = client.nodeList.Values.Last();
response = node.startElection("signOff" + "," + Utils.getDefaultIP());
if (response != null)
{
Console.WriteLine(response);
response = node.propagateCoordinatorMessage(Utils.getDefaultIP());
Console.WriteLine(response);
beautifyOutput();
}
signOffOK = false;
}
catch (Exception e)
{
Console.WriteLine("Exception in master election process ");
}
}
}
else
{
Console.Error.WriteLine("Try to correct servers' socket address"
+ " or clients' socket address");
break;
}
}
else
{
Console.WriteLine("There is no host in the network, try to join at least one");
}
}
else
{
Console.WriteLine("Please first add your server to the network");
}
break;
}
case 3:
{
showNetwork();
break;
}
case 4:
{
break;
}
case 5:
{
server.stop();
Console.WriteLine("DONE");
Console.ReadLine();
return;
}
default:
{
break;
}
}
}
}
public void run()
{
// if everything in critical section was OK
// send "release" message to the coordinator
Client client = new Client(Server.getInstance().getSocketAddress(), Utils.getDefaultSocketAddress());
try
{
node = client.nodeList.Values.Last();
node.sendMessage("release", client.getIP());
}
catch (Exception e)
{
Console.WriteLine("Exception while calling method"
+ " RequestProcessor.sendMessage "
+ "with message RELEASE\n");
}
}
static void Main(string[] args)
{
Client client = null;
IRequestProcessor node;
bool joinOK = false;
bool signOffOK = false;
Console.WriteLine("Enter server's socket address - IP:PORT ");
string serverSocketAddress = Console.ReadLine();
while (true)
{
if (Utils.isValidSocketAddress(Utils.getIPFromSocketAddress(serverSocketAddress)))
{
break;
}
else
{
serverSocketAddress = Console.ReadLine();
}
}
Server server = Server.getInstance(serverSocketAddress);
server.start();
while (true)
{
Console.WriteLine("Press ENTER to continue...");
try
{
Console.ReadLine();
showCommands();
}
catch (IOException e)
{
server.stop();
break;
}
int command = int.Parse(Console.ReadLine());
switch (command)
{
case 1:
{
if (server.isNetworkAvailable())
{
Console.WriteLine("Enter socket address of new host in form IP:PORT, that you want to join: ");
string socketAddress = Console.ReadLine();
while (true)
{
if (Utils.isValidSocketAddress(Utils.getIPFromSocketAddress(socketAddress)))
{
if (checkHostEligibility(Utils.getIPFromSocketAddress(socketAddress)))
{
Console.WriteLine("Host is already in the network! Type in another IP:PORT ");
socketAddress = Console.ReadLine();
}
else
{
break;
}
}
else
{
socketAddress = Console.ReadLine();
}
}
try
{
client = new Client(server.getSocketAddress(), socketAddress);
}
catch (Exception e)
{
Console.Error.WriteLine("Error Setting the server url for this client.");
client = null;
}
if (client != null)
{
object response = null;
beautifyOutput();
try
{
node = client.nodeList.Values.Last();
response = node.joinNode(client.getSocketAddress());
Console.WriteLine(response);
try
{
// propagatemessagetoall in java
response = node.propagateJoinRequest(client.getSocketAddress());
Console.WriteLine(response);
checkClients();
beautifyOutput();
joinOK = true;
}
catch (Exception e)
{
Console.Error.WriteLine("Failed to broadcast join request");
}
}
catch (Exception e)
{
Console.Error.WriteLine("Error executing join request, response is null");
}
if (joinOK)
{
Console.WriteLine("Master node Election ");
try
{
node = client.nodeList.Values.Last();
response = node.startElection("join" + "," + client.getIP());
if (response != null)
{
Console.WriteLine(response);
//propagatemessagetoall in java
response = node.propagateCoordinatorMessage(client.getIP());
Console.WriteLine(response);
beautifyOutput();
}
// Master election is done. because of it joinOK is false now.
joinOK = false;
}
catch (Exception e)
{
Console.Error.WriteLine("Failed to broadcast coordinator message");
}
}
}
else
{
Console.WriteLine("Try to correct server's socket address"
+ " or clients' socket address");
break;
}
}
else
{
Console.WriteLine("Please first add your server to the network");
}
break;
}
case 2:
{
if (server.isNetworkAvailable())
{
bool isOneHostAvailable = false;
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
node = client.nodeList.Values.Last();
object response = node.atLeastOneHostAvailable();
isOneHostAvailable = (bool)response;
}
catch (Exception e1)
{
Console.WriteLine("Exception in executing method "
+ "RequestProcessor.atLeastOneHostAvailable");
}
if (isOneHostAvailable)
{
showNetwork();
Console.WriteLine("Enter the node ID to sign it off from the network:");
int nodeIdToSignOff = int.Parse(Console.ReadLine());
while (nodeIdToSignOff == 0)
{
Console.WriteLine("Server cannot be signed off from the network!" + "\n");
Console.WriteLine("Enter the node ID to sign it off from the network: ");
nodeIdToSignOff = int.Parse(Console.ReadLine());
}
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
}
catch (Exception e)
{
Console.Error.WriteLine("Error Setting the server url for this client.");
client = null;
}
if (client != null)
{
object response = null;
beautifyOutput();
try
{
node = client.nodeList.Values.Last();
response = node.signOffNode(nodeIdToSignOff);
Console.WriteLine(response);
try
{
response = node.propagateSignOffRequest(nodeIdToSignOff);
Console.WriteLine(response);
beautifyOutput();
signOffOK = true;
}
catch (Exception e)
{
Console.WriteLine("Failed to broadcast signoff request");
}
}
catch (Exception e)
{
Console.WriteLine("Error executing signoff request, response is null");
}
if (signOffOK)
{
Console.WriteLine("Master Node Election: ");
try
{
node = client.nodeList.Values.Last();
response = node.startElection("signOff" + "," + Utils.getDefaultIP());
if (response != null)
{
Console.WriteLine(response);
response = node.propagateCoordinatorMessage(Utils.getDefaultIP());
Console.WriteLine(response);
beautifyOutput();
}
signOffOK = false;
}
catch (Exception e)
{
Console.WriteLine("Exception in master election process ");
}
}
}
else
{
Console.Error.WriteLine("Try to correct servers' socket address"
+ " or clients' socket address");
break;
}
}
else
{
Console.WriteLine("There is no host in the network, try to join at least one");
}
}
else
{
Console.WriteLine("Please first add your server to the network");
}
break;
}
case 3:
{
showNetwork();
Console.WriteLine("Do you want see address table of each client(Y/N): ");
string prompt = Console.ReadLine();
//check correctness of prompt
while (!(prompt.Equals("Y", StringComparison.InvariantCultureIgnoreCase) || prompt.Equals("N", StringComparison.InvariantCultureIgnoreCase)))
{
Console.WriteLine("Enter just Y or N: ");
prompt = Console.ReadLine();
}
if (prompt.Equals("Y", StringComparison.InvariantCultureIgnoreCase))
{
checkAddressTables();
}
break;
}
case 4:
{
if (server.isNetworkAvailable())
{
bool isOneHostAvailable = false;
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
node = client.nodeList.Values.Last();
object response = node.atLeastOneHostAvailable();
isOneHostAvailable = (bool)response;
}
catch (Exception e)
{
Console.Error.WriteLine("Exception in executing method "
+ "RequestProcessor.atLeastOneHostAvailable");
}
if (isOneHostAvailable) // then propagate start message to all nodes.
{
object response = null;
node = client.nodeList.Values.Last();
try
{
response = node.startDistributedReadWrite();
string reply = (string)response;
beautifyOutput();
Console.WriteLine(reply);
}
catch (Exception e)
{
Console.Error.WriteLine("Exception in executing method "
+ "RequestProcessor.startDistributedReadWrite");
}
showAlgorithms();
Console.WriteLine("Enter synchronization algorithm ID to start: ");
int algorithmID = int.Parse(Console.ReadLine());
switch (algorithmID)
{
case 1:
{
//boolean variable to hold whether or not the algorithm worked
bool isCeMutExOK = false;
// we will start rpc call to do Centralized Mutual Exclusion method.
//create temporarily client.
try
{
node = client.nodeList.Values.Last();
response = node.doCeMutEx();
//print out what is returned
//Console.WriteLine((string)response);
isCeMutExOK = true;
}
catch (Exception e)
{
Console.Error.WriteLine("Exception in execution of RequestProcessor.doCeMutEx() method");
}
//After process has ended all the nodes read the final string from
//master node and write it to the screen
//Moreover they check if all words they added to the string
//are present in the final string. The result of this check
//is also written to the screen.
if (isCeMutExOK)
{
// we will need a temporary client to
// execute readFinalString method
try
{
//execute readFinalString method on server's handler
response = node.readFinalString();
Console.WriteLine((string)response);
}
catch (Exception e)
{
Console.Error.WriteLine("Exception in execution of "
+ "remote readFinalString() method");
}
}
break;
}
case 2:
{
//boolean variable to hold whether or not the algorithm worked
bool isRicartAgrawalaOK = false;
try
{
node = client.nodeList.Values.Last();
response = node.doRicartAgrawala();
//Console.WriteLine((string)response);
isRicartAgrawalaOK = true;
}
catch (Exception e)
{
Console.Error.WriteLine("Exception in execution of remote "
+ "doRicartAgrawala() method");
}
//After process has ended all the nodes read the final string from
//master node and write it to the screen
//Moreover they check if all words they added to the string
//are present in the final string. The result of this check
//is also written to the screen.
if (isRicartAgrawalaOK)
{
try
{
response = node.readFinalString();
Console.WriteLine((string)response);
}
catch (Exception e)
{
Console.Error.WriteLine("Exception in execution of "
+ "remote readFinalString() method");
}
}
break;
}
default:
{
Console.WriteLine("Please enter correct algorithm id ");
break;
}
}
}
else
{
Console.WriteLine("There is no Host in the network, try to join at least one. ");
}
}
else
{
Console.WriteLine("Please first add your server to the network. ");
}
break;
}
case 5:
{
server.stop();
Console.WriteLine("DONE");
Console.ReadLine();
return;
}
default:
{
break;
}
}
}
}
public string receiveMessage(string message, string requesterIP)
{
// if the received message is "request"
if (message.Equals("request", StringComparison.InvariantCultureIgnoreCase))
{
//if critical section is empty, access has to be granted
if (Server.getInstance().isCriticalSectionEmpty())
{
// so send "GRANTED"
Server.getInstance().assignToCriticalSection(requesterIP);
return("GRANTED");
}
else // someone is in the critical section
{
// queue the request, return DENIED
Server.getInstance().queueRequest(requesterIP);
return("DENIED");
}
}
else if (message.Equals("release", StringComparison.InvariantCultureIgnoreCase))
{
// requester is done with critical section
// remove the requesterIP from critical section
Server.getInstance().removeFromCriticalSection(requesterIP);
// if queue is not empty, dequeue first and reply "GRANTED"
if (!Server.getInstance().isQueueEmpty())
{
string newRequesterIP = Server.getInstance().dequeue();
//assign critical section new enterer ip
Server.getInstance().assignToCriticalSection(newRequesterIP);
//print out who is the new enterer
Console.WriteLine("New Critical Section Enterer IP: " + newRequesterIP);
Client client = Server.getInstance().getClientByIP(newRequesterIP);
// get the random English word
string randomEnglishWord = Server.getInstance()
.generateRandomEnglishWord();
// method to write this generated word to
// client's
// buffer to check it later whether or not
// written
// word exists in the resulting master string
client.rememberWord(randomEnglishWord);
try
{
node = client.nodeList.Values.Last();
object reply = node.enterCS(client.getIP(), randomEnglishWord);
Console.WriteLine((string)reply);
}
catch (Exception e)
{
Console.WriteLine("Exception while calling method"
+ " RequestProcessor.enterCS\n");
}
//to prevent deadlock, because the same thread can
//access the sendMessage again
ThreadStart threadDelegate = new ThreadStart(run);
Thread tempThread = new Thread(threadDelegate);
tempThread.Start();
return("GRANTED");
}
else // queue is already empty, so reply GRANTED
{
return("GRANTED");
}
}
else
{
return("GRANTED");
}
}
static void Main(string[] args)
{
Client client = null;
IRequestProcessor node;
bool joinOK = false;
bool signOffOK = false;
Console.WriteLine("Enter server's socket address - IP:PORT ");
string serverSocketAddress = Console.ReadLine();
while(true)
{
if (Utils.isValidSocketAddress(Utils.getIPFromSocketAddress(serverSocketAddress)))
{
break;
}
else
{
serverSocketAddress = Console.ReadLine();
}
}
Server server = Server.getInstance(serverSocketAddress);
server.start();
while (true)
{
Console.WriteLine("Press ENTER to continue...");
try
{
Console.ReadLine();
showCommands();
}
catch (IOException e)
{
server.stop();
break;
}
int command = int.Parse(Console.ReadLine());
switch (command)
{
case 1:
{
if (server.isNetworkAvailable())
{
Console.WriteLine("Enter socket address of new host in form IP:PORT, that you want to join: ");
string socketAddress = Console.ReadLine();
while (true)
{
if (Utils.isValidSocketAddress(Utils.getIPFromSocketAddress(socketAddress)))
{
if (checkHostEligibility(Utils.getIPFromSocketAddress(socketAddress)))
{
Console.WriteLine("Host is already in the network! Type in another IP:PORT ");
socketAddress = Console.ReadLine();
}
else
{
break;
}
}
else
{
socketAddress = Console.ReadLine();
}
}
try
{
client = new Client(server.getSocketAddress(), socketAddress);
}
catch (Exception e)
{
Console.Error.WriteLine("Error Setting the server url for this client.");
client = null;
}
if (client != null)
{
object response = null;
beautifyOutput();
try
{
node = client.nodeList.Values.Last();
response = node.joinNode(client.getSocketAddress());
Console.WriteLine(response);
try
{
// propagatemessagetoall in java
response = node.propagateJoinRequest(client.getSocketAddress());
Console.WriteLine(response);
checkClients();
beautifyOutput();
joinOK = true;
}
catch (Exception e)
{
Console.Error.WriteLine("Failed to broadcast join request");
}
}
catch (Exception e)
{
Console.Error.WriteLine("Error executing join request, response is null");
}
if (joinOK)
{
Console.WriteLine("Master node Election ");
try
{
node = client.nodeList.Values.Last();
response = node.startElection("join" + "," + client.getIP());
if (response != null)
{
Console.WriteLine(response);
//propagatemessagetoall in java
response = node.propagateCoordinatorMessage(client.getIP());
Console.WriteLine(response);
beautifyOutput();
}
// Master election is done. because of it joinOK is false now.
joinOK = false;
}
catch (Exception e)
{
Console.Error.WriteLine("Failed to broadcast coordinator message");
}
}
}
else
{
Console.WriteLine("Try to correct server's socket address"
+ " or clients' socket address");
break;
}
}
else
{
Console.WriteLine("Please first add your server to the network");
}
break;
}
case 2:
{
if(server.isNetworkAvailable())
{
bool isOneHostAvailable = false;
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
node = client.nodeList.Values.Last();
object response = node.atLeastOneHostAvailable();
isOneHostAvailable = (bool) response;
}
catch (Exception e1)
{
Console.WriteLine("Exception in executing method "
+ "RequestProcessor.atLeastOneHostAvailable");
}
if (isOneHostAvailable)
{
showNetwork();
Console.WriteLine("Enter the node ID to sign it off from the network:");
int nodeIdToSignOff = int.Parse(Console.ReadLine());
while (nodeIdToSignOff == 0)
{
Console.WriteLine("Server cannot be signed off from the network!"+ "\n");
Console.WriteLine("Enter the node ID to sign it off from the network: ");
nodeIdToSignOff = int.Parse(Console.ReadLine());
}
try
{
client = new Client(server.getSocketAddress(),
Utils.getDefaultSocketAddress());
}
catch (Exception e)
{
Console.Error.WriteLine("Error Setting the server url for this client.");
client = null;
}
if(client != null)
{
object response = null;
beautifyOutput();
try
{
node = client.nodeList.Values.Last();
response = node.signOffNode(nodeIdToSignOff);
Console.WriteLine(response);
try
{
response = node.propagateSignOffRequest(nodeIdToSignOff);
Console.WriteLine(response);
beautifyOutput();
signOffOK = true;
}
catch(Exception e)
{
Console.WriteLine("Failed to broadcast signoff request");
}
}
catch(Exception e)
{
Console.WriteLine("Error executing signoff request, response is null");
}
if(signOffOK)
{
Console.WriteLine("Master Node Election: ");
try
{
node = client.nodeList.Values.Last();
response = node.startElection("signOff" + "," + Utils.getDefaultIP());
if (response != null)
{
Console.WriteLine(response);
response = node.propagateCoordinatorMessage(Utils.getDefaultIP());
Console.WriteLine(response);
beautifyOutput();
}
signOffOK = false;
}
catch(Exception e)
{
Console.WriteLine("Exception in master election process ");
}
}
}
else
{
Console.Error.WriteLine("Try to correct servers' socket address"
+ " or clients' socket address");
break;
}
}
else
{
Console.WriteLine("There is no host in the network, try to join at least one");
}
}
else
{
Console.WriteLine("Please first add your server to the network");
}
break;
}
case 3:
{
showNetwork();
break;
}
case 4:
{
break;
}
case 5:
{
server.stop();
Console.WriteLine("DONE");
Console.ReadLine();
return;
}
default:
{
break;
}
}
}
}